Auto merge of #13691 - servo:mem-replace, r=emilio

Use mem::replace in take_pseudo_styles.

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1 files changed, 2 insertions, 5 deletions

diff --git a/components/script/layout_wrapper.rs b/components/script/layout_wrapper.rs
index 451cfe82623..bb0aebe73d2 100644
--- a/components/script/layout_wrapper.rs
+++ b/components/script/layout_wrapper.rs
@@ -52,7 +52,7 @@ use selectors::matching::ElementFlags;
 use selectors::parser::{AttrSelector, NamespaceConstraint};
 use std::fmt;
 use std::marker::PhantomData;
-use std::mem::transmute;
+use std::mem::{replace, transmute};
 use std::sync::Arc;
 use std::sync::atomic::Ordering;
 use string_cache::{Atom, Namespace};
@@ -251,10 +251,7 @@ impl<'ln> TNode for ServoLayoutNode<'ln> {
     }
 
     fn take_pseudo_styles(&self) -> PseudoStyles {
-        use std::mem;
-        let mut tmp = PseudoStyles::default();
-        mem::swap(&mut tmp, &mut self.mutate_data().unwrap().per_pseudo);
-        tmp
+        replace(&mut self.mutate_data().unwrap().per_pseudo, PseudoStyles::default())
     }
 
     fn set_pseudo_styles(&self, styles: PseudoStyles) {